No one knows for sure whether Puerto Rico would be a Democrat or Republican state. Voters in PR are members of either the pro-statehood New Progressive Party (the name has nothing to do with the modern use of the word in U.S. politics; it was chosen by lifelong Republican Gov. Luis A. Ferrer to denote economic progress) or the pro-”commonwealth” Popular Democratic Party. A liberal that is pro-statehood will join and vote for the NPP; a conservative that is pro-statehood will join and vote for the NPP; liberal that is anti-statehood will join and vote for the PDP; and a conservative that is anti-statehood will join and vote for the PDP. Relatively few people know what Republicans and Democrats stand for, and if PR became a state and people had to side with one of the national parties it would be a very fluid process, and we don’t know how many of Puerto Rico’s two senators and five representatives would be Democrat or Republican, either in the short or long term.
While virtually no PDP leaders are members of the national GOP, this is for historical, not ideological, reasons (the main statehood party prior to 1968 was affiliated with the GOP and had “Republican” in its name; PDP founder Luis Muñoz Marín was an ally of FDR and JFK, etc.), and many Populares do not beling to either national party; most NPP leaders are members of the GOP, although many prominent ones are Democrats (part of the NPP’s strategy to achieve statehood is to have a seat in the table at both national parties), and prior to the 2012 elections (in which NPP/GOP Mayor Jorge Santini was upset in San Juan), 6 of the 8 largest cities had Republican mayors (now it’s 5 out of 8).
The typical Puerto Rico voter is socially conservative (pro-life, pro-marriage), economically populist (protectionist, wary of big business), pro-military, and more tolerant of corruption or personal foibles than your average bear; they also have no interest in amnesty for illegal aliens, and don’t have a very high opinion of the illegal aliens from the Dominican Republic that have been arriving in PR over the past 30 years. The most similar state electorate statewide would be Louisiana’s, particularly prior to the Obama years; LA voted for Nixon in 72, Carter in 76, Reagan in 80 and 84, Bush in 88, Clinton in 92 and 96, and Bush in 2000 and 2004, and PR likely would have voted pretty much the same way as LA (except that Gore likely would have beaten Bush). The biggest difference between LA and PR is the lack of racial polarization in PR, where blacks don’t vote as a block (in fact, the president of the PR Republican party is the black mayor of Aguadilla). Puerto Ricans that have moved to Central Florida over the past 25 years pretty much have been swing voters, voting for Gore and Nelson in 2000, Jen in 2002, W and Mel in 2004, Crist and Nelson in 2006, Obama in 2008, Rubio in 2010 and Obama and Nelson in 2012; one needs to keep in mind that about 1/3 of Puerto Ricans in Central FL didn’t move there from PR, but are second- or third-generation “Newyorricans” from urban areas in NY, NJ, CT, MA or IL (and those vote heavily Democrat).
So if anyone tells you that he knows how Puerto Rico will vote a decade or two after it becomes a state, take it with a huge pillar of salt. Ultimately, of course, the decision whether to make Puerto Rico a state should rest not on political calculations, but on basic fairness. Puerto Rico’s 3.6 million U.S. citizens should have the right to elect the members of Congress that legislate over them and for the president who can send them to war.
The (seemingly impossible to predict) percentage of PDP supporters that would be Republicans seems to be the key to the whole thing.
I wish Puerto Rico had a Presidential preference poll or something, that would be useful data.